By means of low-temperature(10K)Fourier transform infrared absorption spectroscopy,the kinetics of nitrogen indiffusion in Czochralski(CZ)silicon annealed 8t 1150-1250°C in nitrogen ambient is investigated.Moreover,the nitrogen diffusivities in CZ silicon at elevated temperatures deduced herein are in good agreement with those previously obtained in float-zone silicon,thus leading to the conclusion that the nitrogen indiffusion in CZ silicon at elevated temperatures is via nitrogen pairs.